Pigmented Primer for N-Acyl Urea Coatings
Solution Overview
Problem
Aromatic carbodiimides have not found suitable applications in coatings, particularly in forming coatings with excellent anticorrosion properties, despite their utility in peptide and organic synthesis and as acid scavengers for ester-based polymers.
Innovation Solution
A pigmented primer composition comprising a polycarbodiimide-polyurethane hybrid, an acid functional polymer, an organic solvent, a pigment, and an inorganic filler, which forms an n-acyl urea coating with improved corrosion resistance on substrates like unpolished cold rolled steel, aluminum, or galvanized steel, using specific structural ratios and reaction conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If aromatic carbodiimides are used in coatings, then anticorrosion properties can be improved, but suitable application methods have not been established
Solution Approach 1:
The patent changes the chemical structure parameters of carbodiimides by introducing specific alkoxy groups at defined positions (x, Y, z ratios) to create a polycarbodiimide-polyurethane hybrid that is suitable for coating applications while maintaining excellent anticorrosion properties
Solution Approach 2:
The patent creates a composite material system by combining polycarbodiimide-polyurethane hybrid with acid functional polymer in a pigmented primer composition, enabling both suitable application characteristics and superior corrosion resistance
2Reliability
If polycarbodiimide-polyurethane hybrid is used with acid functional polymer, then corrosion resistance is improved to 2 to 10 on steel substrates, but formulation complexity increases
Solution Approach 1:
The patent merges polycarbodiimide and polyurethane components into a single hybrid polymer system that reacts with acid functional polymer to form n-acyl urea coating, simplifying the overall formulation while achieving enhanced corrosion resistance
Solution Approach 2:
The patent optimizes the structural parameters (x, Y, z ratios) of the polycarbodiimide-polyurethane hybrid to achieve maximum corrosion protection with minimal formulation complexity
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The n-acyl urea coating exhibits corrosion resistance of 2 to 10 as determined by ASTM standards, providing effective protection against corrosion on various steel substrates.
Implementation Method 1
A pigmented primer composition for forming an n-acyl urea coating that resists corrosion on a substrate... comprises a polycarbodiimide-polyurethane hybrid... an acid functional polymer... reacting to form the n-acyl urea coating
Data Source
AI summary
This disclosure provides a pigmented primer composition for forming an n-acyl urea coating on a substrate. The pigmented primer composition includes a polycarbodiimide-polyurethane hybrid. The pigmented primer composition also includes an acid functional polymer and an organic solvent, and includes less than or equal to 10 weight percent of water based on a total weight of the pigmented primer composition. The pigmented primer composition also includes a pigment, an inorganic filler, and less than about 100 parts by weight of toluene diisocyanate per one million parts by weight of the pigmented primer composition. The n-acyl urea coating exhibits corrosion resistance of 2 to 10 as determined using ASTM B117 and ASTM D-1654-08 on a substrate that is unpolished cold rolled steel, aluminum, or galvanized steel.